What's the order of magnitude of requests the API serve per day? I've build a demo on top of HN data and I had a feeling that most of it is quite static and could easily be cached behind something like cloudflare
Yes to the other bit.
https://github.com/searchableguy/hackernews_graphql
It is still incomplete though because I remember you said I could not scrape the site beyond robot.txt limits which would be too less for the use case because I wanted to provide write functionality so I gave up.
Maybe people can host a caching relay and a layer like graphql on top as an unofficial way to lessen the burden on the firebase API (it's a pain to use anyway).